SAT Math 9.5 Algebra and Functions

SAT Math 9.5 Algebra and Functions

AlgebraFactoring
Quadratic Equations
Algebra IIQuadratic Equations
Algebra and FunctionsSolving Quadratic Equations by Factoring
LanguageEnglish Language
Passport to Advanced MathQuadratic and exponential functions (word problems)
Product TypeSAT Math
Quadratic EquationsQuadratic Equations
SAT MathAlgebra and Functions

Transcript

00:37

Let’s take a closer look at the second requirement.

00:40

This just means that if we plugged the value (x + 1) into the function,

00:44

which we’re given in the first requirement, we can solve for x.

00:47

To solve this equation, we’re first going to have to turn it back into a polynomial.

00:51

So, we expand (x + 1) squared first.

00:55

By applying foil, we turn (x + 1) squared into x squared + 2x + 1.

01:03

Then, we distribute -6 into the second parentheses. We get -6x - 6.

01:10

Now we can combine like terms. There’s only one x squared term, so that stays by itself.

01:15

However, we have both 2x and -6x, so we can combine those to -4x.

01:20

Then, all of the constants add to +3. Great, we have a polynomial!

01:24

To be more specific… it's a quadratic.

01:27

We can just stick this puppy into the quadratic formula and come out with the answer.

01:31

Plugging in our values, we get that x is equal to 4 plus or minus the square root of 16 – 12 over 2.

01:40

This simplifies to 4 plus or minus 2 over 2. The possibilities are 1 or 3.

01:47

That's our answer either 1 or 3.